In order to form a complete triax of accelerometers or gyros where all mechanisms are the same, at least one of the mechanisms must be mounted in a complex custom package or the die must be edge mounted.
Various micromechanical devices, such as micromechanical gyroscopes, require hermetic sealing in order to ensure long-term, accurate operation. Conventional hermetic sealing is achieved by mounting the device in a hermetically-sealed housing or enclosure. Input and output electrical connections to and from the enclosed device are provided by embedding conductors through portions of the enclosure to permit conductive traces or wires to be connected to the device.
However, this type of hermetically-sealed enclosure tends to be relatively costly. Moreover, tolerances associated with mounting the device in the enclosure may affect the accuracy of a device, which is sensitive to spatial orientation. For example, some inertial systems utilize three inertial rate sensors arranged orthogonally with respect to one another. When each such sensor is mounted in a respective hermetically-sealed enclosure, tolerances associated with mounting each sensor in the respective enclosure, as well as tolerances associated with mounting the enclosed packages in orthogonal relationship with respect to each other, may adversely affect the accuracy of the system.